Lightweight hybrid material truck hoods

ABSTRACT

The present disclosure provides a truck hood including a metal hood skin including at least an upper portion and a sidewall portion; and a frame supporting at least a portion of the metal hood skin including polymer and aluminum reinforcements. The polymer reinforcements include a front hood stiffener member positioned at a front end portion of the metal hood skin, a rear hood stiffener member positioned at a rear end portion of the metal hood skin and hood corner longitudinal members connecting the front hood stiffener member to the rear hood stiffener member. The aluminum reinforcements include front and rear frame extruded members positioned along the sidewalls of the metal hood skin and an arch extruded reinforcement positioned at the wheel arch. In one aspect of the disclosure, the truck hood further includes a pair of fenders formed of a metal skin that may be reinforced by a polymer fender mat.

CROSS-REFERENCE TO RELATED APPLICATION

This is a divisional patent application of U.S. patent application Ser.No. 11/467,627 filed on Aug. 28, 2006.

FIELD OF THE INVENTION

The present disclosure relates to the lightweight truck hoods. Morespecifically, the disclosure provides a truck hood made from aluminumand having reinforcement members that may be made from polymers andaluminum.

BACKGROUND OF THE INVENTION

Vehicles in general, and trucks in particular, are always in need ofimproved fuel efficiency. Such improved fuel efficiency may be achievedby making the vehicles out of more lightweight components. However, thestrength and structural integrity of the components must be maintainedas their weight is reduced. Additionally, reduced weight is desirable incomponents that must be raised to service the vehicle, or to accessother interior portions of the vehicle, for example the vehicle's hood.

Many presently available truck hoods are made from either sheet metal orpolymer fiber composites. Hoods made from sheet metal typically includeseveral components added to the hood panel itself to provide structuralsupport and durability. These components increase the weight and cost ofmanufacture of the hood.

Fiberglass reinforced plastic (composite) hoods require slow, laborintensive manufacturing processes. More specifically, manufacturing offiberglass reinforced plastic hoods typically includes the steps ofproviding a wooden mold, spraying a fiberglass media into the mold, andthen applying a polymer resin. Each of these steps are manual laborintensive steps resulting in high production time for a singular hood.Such composite hoods must often be thicker, typically on the order of6.0 mm or greater, to provide the required strength.

To provide the required strengths in fiberglass reinforced plastic(composite) hoods, the steps of spraying the fiberglass media andapplying the polymer resin are repeated, which in turn results inincreased weight. Additionally, components such as truck hoods areproduced in relatively small volumes, and in several configurations. Thelow production volume limits the number of manufacturing and assemblyprocesses that are economically viable.

FIGS. 1-5 illustrate a typical reinforcement structure presently usedwith fiberglass reinforced plastic truck hoods. The reinforcementstructure 10 is fanned of fiberglass reinforced plastic and includes afront reinforcement 12 having a generally rectangular configuration,defined by the top 14, bottom 16, and sides 18, 20. The right side 18and left side 20 each define a headlight reinforcement portion 22, 24,respectively, extending outward therefrom. The remainder of theheadlight reinforcement is a separate piece, with the left sideheadlight reinforcement 26 illustrated in FIG. 3, and the right sideheadlight reinforcement being a mirror image of the left sidereinforcement 26.

A right side reinforcement 28 and left side reinforcement 30 extendrearward from the front reinforcement 12. The right side reinforcement28 is a mirror image of the left side reinforcement 30. Each of the leftside reinforcement 30 and right side reinforcement 28 includes arearwardly extending portion 32, corresponding to the lower side edgesof the hood, a vertical portion 34 extending upward from the back end ofthe rearwardly extending portion 32, and a top portion 36 extendinghorizontally from the vertical portion 34, and corresponding to the toprear edge of the hood. Presently available hoods may also include aplenum 38, for reinforcing an air intake located on the top of the hood,and leading to the engine, as depicted in FIG. 5.

Such presently available fiberglass reinforced plastic truck hoodstherefore require a large number of reinforcements to properlystrengthen the hood, thereby increasing weight, cost, and the timerequired to manufacture the hood.

In light of the above, there is a need for a truck hood or other vehiclecomponent having lighter weight than presently available components,while maintaining sufficient strength. There is a further need for atruck hood or other vehicle components that may be manufactured byrelatively inexpensive manufacturing methods. Such a vehicle componentwill not only be more cost effective to manufacture, but will decreasethe costs associated with operating the vehicle upon which it isinstalled.

SUMMARY OF THE INVENTION

Generally speaking, the present disclosure provides a vehicle bodycomponent such as a truck hood having a metal skin reinforced by aplurality of polymer and metal reinforcements secured to the interior ofthe skin.

The truck hood may include:

a metal hood skin including at least an upper portion and a sidewallportion; anda frame supporting at least a portion of the metal hood skin, the frameincluding a polymer reinforcement secured to an interior side of thehood skin, the polymer reinforcement including a front hood stiffenermember positioned at a front end portion of the metal hood skin, a rearhood stiffener member positioned at a rear end portion of the metal hoodskin and hood corner longitudinal members connecting the front hoodstiffener member to the rear hood stiffener member and positioned alongat a transition between the upper portion and sidewall portion of themetal hood skin.

In one embodiment, the metal skin may be formed of two skin portionssecured to each other, a first hood skin portion including the upper andsidewall portions of the metal hood skin and a second hood skin portionincluding a pair of fenders.

In one embodiment, the truck hood further includes an arch extrudedreinforcement (also referred to as arch extrusion), preferably beingaluminum, reinforcing the connection between the first hood skin portionincluding the upper and sidewall portions of the metal hood skin andsecond hood skin portion including a pair of fenders. The arch extrudedreinforcement may have a geometry corresponding to the wheel arch of awheel well.

In one embodiment, the truck hood may further include front frame andrear frame extruded members, preferably being aluminum, positioned tosupport at least the sidewall portion of the metal hood skin. The frontand rear frame extruded member form a triangular truss structure with abase provided by the arch extruded reinforcement and with an apexconnected to the hood corner longitudinal members. The truck hood mayfurther include a node casting, preferably composed of aluminum, at theapex of the front and rear extruded members including a springattachment member; a rear hood support casting connected to the rearextruded member; and a pivot member casting connected to the archextruded member and positioned at the front end portion of the metalhood skin.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

The following detailed description, given by way of example and notintended to limit the disclosure solely thereto, will best beappreciated in conjunction with the accompanying drawings, wherein likereference numerals denote like elements and parts, in which:

FIG. 1 is a perspective view of the reinforcements presently utilizedwith fiberglass reinforced polymer truck hoods, as known in the priorart.

FIG. 2 is a perspective view of a front reinforcement presently usedwith fiberglass reinforced polymer truck hoods as known in the priorart.

FIG. 3 is a perspective view of a headlight reinforcement presently usedwith fiberglass reinforced polymer truck hoods as known in the priorart.

FIG. 4 is a perspective view of a side reinforcement presently used withfiberglass reinforced polymer truck hoods as known in the prior art.

FIG. 5 is a perspective view of a plenum presently used with fiberglassreinforced polymer truck hoods as known in the prior art.

FIG. 6 is a perspective view of one preferred embodiment of a truck hoodin accordance with the present disclosure, in which the lower hood panelof the truck hood is included so that it may be made in the same coloras the remainder of the truck hood.

FIG. 7 is a perspective view of a lower hood panel, in accordance withthe present disclosure.

FIG. 8 is a perspective view of another preferred embodiment of a truckhood in accordance with the present disclosure, in which the lower hoodpanel is omitted so that it may be provided as part of the grille.

FIG. 9 is an exploded view of a truck hood in accordance with thepresent disclosure.

FIG. 10 is a perspective view of one embodiment of a truck hoodreinforcing structure in accordance with the present disclosure.

FIG. 11 is a perspective view of one embodiment of the front hoodstiffener member and rear hood stiffener member of the polymerreinforcement and one embodiment of a pivot cast member, in accordancewith the present disclosure.

FIG. 12 is an interior side view of the sidewall portion of oneembodiment of a truck hood in accordance with the present disclosure.

FIGS. 13 a-13 b are perspective views of the connection between thefirst portion of the hood skin and the second portion of the hood skin,in which the second portion of the hood skin includes fenders.

FIG. 13 c is a section view of a truck hood and fender structure inaccordance with the present disclosure.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 6 depicts one embodiment of a truck hood 40 in accordance with thepresent disclosure. Preferably, the truck hood 40 is to be employed inlong haul trucks, such as Class 8 truck applications. The truck hood 40includes a hood skin having a top or upper surface 41, a right sidewall42 joined to the upper surface 41, and a left sidewall 43 joined to theother side of the upper surface 41. The upper surface 41 and sidewalls42, 43 of the metal hood skin may be made from any metal having suitablestrength and weight, with preferred metals including aluminum, such asAluminum Association 3XXX, 5XXX or 6XXX series aluminum alloy sheet,preferably having a thickness of about 1.5 mm to about 2.5 mm. The metalskin is preferably formed into a desired shape by any sheet metalforming process, such as stamping.

Fender skin structures 44, 45 may be formed integrated into the sidewallportions 42, 43 of the hood skin to provide a singular structure or maybe detachably connected to the sidewall portions 42, 43 of the hoodskin. Each of the fender skin structures 44, 45 may include a headlightopening 46, 47 therein. The sidewall portions 42, 43 and fenderstructures 44, 45 may be joined by presently available methods such asspot welding, other forms of welding, or other forms of mechanicalfastening, such as nut and bolt arrangements and riveting.

In one embodiment, the front edges 48, 49 of the sidewalls 42, 43, alongwith the front edge 50 of the top surface 41, define a space 51structured to receive a grille. In the embodiment of FIG. 6, a frontpanel 52 is also included so that it may be made in the same color asthe remainder of the truck hood 40. One embodiment of a front panel 52is depicted in FIG. 7. The front panel 52 may be connected between theopposing lower front corners of the fender skin structures 44, 45 bymechanical attachment, including nut and bolt arrangements, rivets andcombinations thereof.

FIG. 8 depicts another embodiment of a hood structure 40 provided inaccordance with the present disclosure, in which the front panel isomitted so that it may be provided as part of the grille, and may havethe same finish or chrome plating as the grille.

FIG. 9 depicts an exploded view of one embodiment of a hood structure40, in accordance with the present disclosure. The hood structure 40includes a metal hood skin 53, a frame 54 supporting at least a portionof the metal hood skin 53, and a reinforced fender assembly 55.

FIG. 10 depicts one embodiment of a frame 54 for supporting at least aportion of the metal hood skin 53. In one embodiment, the frame 54includes a polymer reinforcement secured to the interior side of thehood skin 53, in which the polymer reinforcement includes a front hoodstiffener member 56 positioned corresponding to a front end portion ofthe metal hood skin 53, a rear hood stiffener member 57 positionedcorresponding to a rear end portion of the metal hood skin 53 and hoodcorner longitudinal members 58 connecting the front hood stiffenermember 56 to the rear hood stiffener member 57 and positionedcorresponding, to the transition between the upper surface 41 andsidewall portions 42, 43 of the metal hood skin 53. In one embodiment,the front hood stiffener member 56 and the rear hood stiffener member 57have a generally U-shaped geometry corresponding to the interior surfaceof the metal hood skin 53.

Referring to FIG. 11, one preferred polymer reinforcement front hoodstiffener member 56 includes a top portion 59 having a left side portion60 and right side portion 61 depending downward therefrom. The topportion 59, left side portion 60, and right side portion 61 define anopening 62 therein, structured to receive a grille. The left sideportion 60 and right side portion 61 each includes a headlight supportportion 62, 63, preferably in a lower portion of the left side portion60 and right side portion 61. One preferred polymer reinforcement rearhood stiffener member 57 includes top portion 64 having a right sideportion 65 and left side portion 66 depending downward therefrom. In oneembodiment, the right side portion 65 and left side portion 66 of therear hood stiffener member 56 have an increased thickness correspondingto the portions of the metal hood skin 53 requiring additionalreinforcement. The rear hood stiffener member 57 may further include aplurality of vents 67 defined in the center of the top portion 64.

Referring to FIG. 10, the hood corner longitudinal members 58 connectingthe front hood stiffener member 56 to the rear hood stiffener member 57are positioned corresponding to the transition between the upper surface41 and sidewall portions 42, 43 of the metal hood skin 53. In oneembodiment, the hood corner longitudinal member 58 is configured toprovide the base of a triangle formed between the hood longitudinalmember 58, the upper surface 41 of the metal skin 53, and the sidewall42, 43 of the metal skin in a manner that reinforces the transitionbetween the upper surface 41 and the sidewalls 53. Preferably, the fronthood stiffener member 56 and the rear hood stiffener member have athickness on the order of about 3.0 mm.

The polymer reinforcements, including the front hood stiffener member56, rear hood stiffener member 57, and hood corner longitudinal members58, may be made from any suitable polymer, with suggested materialsincluding thermoplastic and thermoset sheet, thermoplastic and thermosetmolding pellet, as well as sheet molding compounds. In one highlypreferred embodiment, the polymer includes nylon containing polymers,one preferred polymer including greater than 50.0 weight %polyhexamethylene adipamide (nylon 66), greater than 30.0 weight % inertfiller, less than 3.0 weight % carbon black, less than 3.0 weight %titanium dioxide, and less than 1.0 weight % of colorants, lubricantsand stabilizers. Another preferred polymer includes than 60.0 weight %polyhexamethylene adipamide (nylon 66), greater than 30.0 weight % inertfiller, less than 1.0 weight % carbon black, and less than 15.0 weight %of short glass fibers. Another preferred polymer is Minion™ availablefrom Dupont Inc.

The polymer reinforcements may be formed from processes such as moldingand vacuum thermoforming, with vacuum thermoforming being most preferredfor low volume production. The polymer reinforcements may be attached tothe metal skin by either mechanical fasteners or by adhesives.Preferably, the polymer reinforcements occupy about 20% to about 30% ofthe interior surface area of the truck hood 40, and comprise about 25%to about 35% of the total weight of the truck hood 40.

Referring to FIG. 10, in one embodiment, the frame 54 may furtherinclude an arch extruded reinforcement 68, preferably of aluminum,reinforcing a connection between the metal hood skin 53 and thereinforced fender structure 55, wherein the arch extruded reinforcement68 corresponds to the wheel arch of a wheel well. Preferably, the archextruded reinforcement 68 is formed of a 6XXX series aluminum, mostpreferably being an extrusion of Aluminum Association 6061-T6. For thepurposes of this disclosure, the term “extrusion” is meant to definethat the member is made using an extrusion process, in which theextrusion has a substantially uniform cross section dictated by theextrusion die. In one embodiment, the arch extruded reinforcement 68 hasa thickness on the order of about 2.0 mm.

In one embodiment of the present disclosure, the frame 54 furtherincludes front frame and rear frame extruded members 69, 70, preferablyof aluminum, positioned to support at least the sidewall portion 42, 43of the metal hood skin 53. The front and rear frame extruded member 69,70 form a triangular structure with a base provided by the arch extrudedreinforcement 68 and with an apex 71 connected to the hood cornerlongitudinal members 58. Preferably, the front frame and rear frameextruded members 69, 70 are formed of a 6XXX or 5XXX series aluminum,most preferably being an extrusion of Aluminum Association 6061-T6. Inone embodiment, the arch extruded reinforcement 68 has a thickness onthe order of about 2.0 mm.

FIG. 12 is an interior side-view of the sidewall 42 portion of oneembodiment of the inventive truck hood and depicts the portion of theframe 54 that supports at least the sidewalls 42 of the metal skin 53.The portion of the frame 54 supporting the sidewalls 42 includes atleast the front and rear frame extruded member 69, 70.

In one embodiment, the truck hood 40 further includes a node 71 at theapex of the front and rear extruded members 69, 70 including a springattachment member. Preferably, the node 71 is formed from a metal sheet,preferably including a 5XXX or 6XXX series alloy, such as Aluminum.Association 6061 treated to T4 temper. Alternatively, the node 71 is acasting of Aluminum Association A356-T6. In one embodiment, the truckhood 40 further includes a rear hood support casting 72 connected to therear extruded member 70. The rear hood support casting 72 is configuredto act a support for the truck hood 40 when in the closed position.Preferably, the rear hood support casting 72 is cast from a 3XX seriesalloy, such as Aluminum Association A356-T6.

In one embodiment, the truck hood 40 further includes a pivot membercasting 73 connected to the arch extruded reinforcement 68 andpositioned at the front end portion of the metal hood skin 53. The pivotcasting 73 may be of any geometry that would support the operationweight of the hood 40 when open and closed. Preferably, the pivot membercasting 73 is cast from a 3XX series alloy, such as Aluminum AssociationA356-T6. In one embodiment, the truck hood 40 may include a cross brace74 positioned between the pivot member castings 73, wherein the crossbrace 74 is preferably an extruded aluminum member, as depicted in FIG.9. In a preferred embodiment, the cross brace 74 is extruded of anAluminum Association 6XXX alloy, most preferably being AluminumAssociation 6061-T6.

FIGS. 13A-13C, depict one embodiment of a reinforced fender structure55, in which the connection between the metal hood skin 53 and thefender structure 55 is strengthened by the arch extruded reinforcement68. In one embodiment, the reinforced fender structure 55 includesfender skin structures 44, 45, a weatherstrip component 75 and areinforcing fender mat 76.

Preferably, the fender skin structures 44, 45 include a stamped metalskin and may be made from any metal having suitable strength and weight,with preferred metals including 3XXX, 5XXX or 6XXX series aluminum alloysheet having a thickness of about 1.5 mm to about 2.5 mm, preferablybeing 2.0 mm. The metal fender skin structures 44, 45 are preferablyformed into a desired shape by any sheet metal forming process such asstamping. The weatherstrip component 75 is preferably a polymermaterial, such as Polyvinyl chloride (PVC).

The reinforcing fender mat 76 may be formed, preferably molded, from anysuitable polymer, with suggested materials including thermoplastic andthermoset sheet, thermoplastic and thermoset molding pellet, as well assheet molding compounds. In one highly preferred embodiment, the polymerof the reinforced fender mat 76 includes nylon containing polymers, onepreferred polymer including greater than 50.0 weight % polyhexamethyleneadipamide (nylon 66), greater than 30.0 weight % inert filler, less than3.0 weight % carbon black, less than 3.0 weight % titanium dioxide, andless than 1.0 weight % of colorants, lubricants and stabilizers. Anotherpreferred polymer includes than 60.0 weight % polyhexamethyleneadipamide (nylon 66), greater than 30.0 weight % inert filler, less than1.0 weight % carbon black, and less than 15.0 weight % of short glassfibers. Another preferred polymer is Minlon™ available from Dupont Inc.The polymer reinforcing fender mat 76 may be formed from processes suchas molding and vacuum thermoforming and may have a thickness on theorder of 5.0 mm.

Referring to FIG. 13B, in one embodiment, the reinforced fenderstructure 55 is connected to the sidewalls 42, 43 of the truck hood 40by engagement between the polymer reinforcing fender mat 76 and thesidewall portions 42, 43. The engagement between the polymer reinforcingfender may 76 and the sidewall portions 42,43 may be provided bymechanical attachment, including nut and bolt arrangements, rivots andcombinations thereof; by welding operations, such as spot welding; oradhesively.

Referring to FIG. 13C, in one embodiment, the engagement of the fenderskin structure 44 and the polymer reinforcing mat 76 is strengthened bythe arch extruded reinforcement 68, wherein the polymer reinforcing mat76 is mechanically attached to the arch extruded reinforcement 68through the sidewall portion 42, 43 of the hood skin 53. In oneembodiment, the polymer weatherstrip 75 provides sealing engagementbetween first hood skin portion including the upper and sidewallportions 41, 42, 43 and the second hood skin portion including thefender skin structure 44, 45.

As compared to the prior art hood of FIGS. 1-5, the number of partsincluded in the truck hood 40 of the present disclosure has been reducedfrom 21 to 10, providing for a reduction in weight from about 167 lbs.to about 90 lbs. Part of this weight savings is derived from thedecreased need to reinforce an aluminum skin as compared to a polymerskin. In one embodiment, it is only necessary for the polymerreinforcements to occupy about 20% to about 30% of the interior surfaceof the truck hood 40, 66, and to comprise about 25% to about 35% of thetotal weight of the truck hood 40, 66.

The present disclosure may provide a truck hood having a better strengthto weight ratio than presently available truck hood structures.

The present disclosure may further provide a truck hood component thatis inexpensive to manufacture using manufacturing methods that are costeffective for low volume production.

The present disclosure may further provide a truck hood component thatfacilitates access to those portions of the vehicle that it covers bybeing easier to raise and lower due to its light weight.

The present disclosure may also provide a vehicle body component madefrom fewer subcomponents.

1. A truck hood, comprising: a metal hood skin including at least anupper portion and a sidewall portion; and a frame supporting at least aportion of the metal hood skin, the frame including a polymerreinforcement secured to an interior side of the hood skin, the polymerreinforcement including a front hood stiffener member positioned at afront end portion of the metal hood skin, a rear hood stiffener memberpositioned at a rear end portion of the metal hood skin and hood cornerlongitudinal members connecting the front hood stiffener member to therear hood stiffener member and positioned along at a transition betweenthe upper portion and sidewall portion of the metal hood skin.
 2. Thetruck hood component according to claim 1, wherein the metal skincomprises at least two skin portions secured to each other, a first hoodskin portion including the upper and sidewall portions of the metal hoodskin and a second hood skin portion including a pair of fenders.
 3. Thetruck hood component according to claim 1, wherein the metal skin ismade from aluminum.
 4. The truck hood component according to claim 1,wherein the polymer reinforcement comprises thermoplastic sheet,thermoset sheet, thermoset pellet, thermoplastic pellet, sheet moldingcompound or combinations thereof.
 5. The truck hood component accordingto claim 2, wherein the first hood skin portion and the second hood skinportion are connected by welds or mechanical fasteners.
 6. The truckhood component according to claim 5, further comprising an arch extrudedreinforcement reinforcing a connection between the first hood skin andsecond hood skin, wherein the arch extruded reinforcement corresponds tothe wheel arch of a wheel well.
 7. The truck hood component according toclaim 6, wherein the arch extruded reinforcement comprises a 6XXX seriesaluminum.
 8. The truck hood according to claim 6, further comprising apolymer weatherstrip in sealing engagement to the first hood skinportion and the second hood skin portion.
 9. The truck hood according toclaim 6, further comprising a polymer fender mat reinforcing the secondhood skin component.
 10. The truck hood according to claim 6, furthercomprising front frame and rear frame extruded members positioned tosupport at least the sidewall portion of the metal hood skin.
 11. Thetruck hood according to claim 10, wherein the front and rear frameextruded member form a triangular structure with a base provided by thearch extruded reinforcement and with an apex connected to the hoodcorner longitudinal members.
 12. The truck hood according to claim 11wherein the front and rear frame extruded members comprises a 6XXXseries aluminum.
 13. The truck hood according to claim 11 furthercomprising a pivot member casting connected to the arch extrudedreinforcement and positioned at the front end portion of the metal hoodskin.
 14. The truck hood according to claim 13, further comprising anode casting at the apex of the front and rear extruded membersincluding a spring attachment member and a rear hood support castingconnected to the rear extruded member.
 15. The truck hood according toclaim 14, wherein at least one of the node casting, the rear hoodsupport casting, and the pivot member casting comprise a 3XX seriesaluminum alloy.
 16. The truck hood according to claim 13, furthercomprising an extruded cross brace disposed between the pivot membercastings.